For the printing of small-format printing sheets it is a known practice to use printing units in which the cylinders participating in the printing, such as a plate cylinder, a rubber cylinder and a printing cylinder, have different diameters. Thereby mechanical expenditure can be saved in the field of the printing plates, of the rubber blankets or of the printing cylinder.
From DE-PS 24 35 203 a sheet-fed rotary printing machine is known. It has, in the most diverse configurations, plate cylinders with simple or single diameter, a rubber cylinder with multiple diameter, and a printing cylinder with single diameter. Thereby from differently installable printing units from a particular plate cylinder, a partial image of a print image can be printed on one of several segments of the rubber cylinder. Simultaneously, this print image can be printed on a printing sheet guided on the printing cylinder, in which process the printing sheet with the printing cylinder revolves in correspondence to the movement of the segments of the rubber cylinder and is printed from this latter.
In U.S. Pat. No. 3,347,160 there is described an ink roller device for a multicolor rotary offset printing machine. This printing machine has a plate cylinder and rubber cylinder in each case with multiple diameter on which there is allocated a printing cylinder with single diameter. In the printing the printing plate consisting of several image parts is generated on the plate cylinder of several cycled inking and moistening mechanisms, transferred to the multiply large rubber cylinder and printed on a printing sheet guided on the printing cylinder. There the printing cylinder rotates a number of times corresponding to the diameter ratio between rubber cylinder and printing cylinder until all the print image parts are transferred to the printing sheet. This multiple color printing machine is suited for the so-called proof printing. The disadvantage in these devices is that they can be produced, to be sure, as single print units, but that the expenditure for the printing of images that contain more color than the particular printing machine permits is very high. These printing machines, accordingly, are suited only for special printing processes.